A pilot valve interstage variable damper

Abstract

A pilot valve interstage variable damper, comprising a special hydraulic cylinder, a variable cross-section piston device and a slide rod. It is used to connect the pilot stage and the main valve stage of the valve. The special hydraulic cylinder is matched with the variable cross-section piston device and the slide rod through left and right cavities. The cavity walls of the left and right cavities are respectively provided with rectangular through holes. The left through hole is provided with a narrow radial oil outlet. The upper wall of the right through hole is provided with a flexible mountain-shaped damping device. The slide rod forms a T-shaped structure through the rod part and the slide head. The slide head is matched with the right through hole in clearance. When the slide head enters the edge position at both ends, it is blocked by the hole wall and the flexible mountain-shaped damping device to drive the hydraulic cylinder to move and generate resistance. When it is in other positions, no resistance is generated. Through the damper, resistance can be provided when the pilot valve core and the main valve core are connected at the same time, the influence of the pilot valve core vibration on the main valve core is offset to a certain extent, and the smoothness of the movement of the pilot valve when it works normally is ensured.

Description

Technical Field

[0001] This invention belongs to the field of fully automated products and relates to a pilot valve stage variable damper. Background Technology

[0002] In the field of hydraulic engineering, hydraulic valves are a key type of control element used to regulate the flow and pressure of fluids to meet the requirements of various industrial and mechanical applications.

[0003] For example, pilot valves are typically used to control the operation of main hydraulic valves to ensure that the valve spool remains stable in the required position. However, due to changes in fluid pressure or other operating conditions in the hydraulic system, the control pressure of the pilot valve may not be maintained at the ideal level, causing the valve spool of the main hydraulic valve to produce unwanted chatter or vibration.

[0004] Valve spool vibration in hydraulic valves can lead to unstable valve opening and even mechanical damage. While dampers can alleviate valve spool vibration to some extent, conventional dampers typically use a combination of a hydraulic cylinder and a spring to generate damping. The damping value generated by the hydraulic cylinder varies with its displacement, making it impossible to guarantee a constant damping value, and it can also hinder the normal movement of the valve spool. Summary of the Invention

[0005] To solve the above problems, the technical solution adopted by the present invention is: a pilot valve stage variable damper, comprising...

[0006] Special-type hydraulic cylinders, variable cross-section piston devices, and slide bars;

[0007] The special hydraulic cylinder includes two non-connected chambers, forming a left chamber and a right chamber;

[0008] The cavity contains hydraulic oil;

[0009] The left and right chamber walls of the special hydraulic cylinder are respectively provided with rectangular through holes, forming a left through hole and a right through hole; wherein, damping devices are provided at both ends of the right through hole near the edge;

[0010] The variable cross-section piston device is a 4-segment shaft, including shaft d1, shaft d2, shaft d3 and shaft d4. The diameters of the 4-segment shaft are d1, d2, d3 and d4 respectively, and the diameter relationship satisfies d4 = d2 > d1 > d3.

[0011] The d1, d2, d3, and d4 axes are components of the cross-section piston device;

[0012] The inner diameter of the left cavity opening is the same as the maximum diameter of the variable cross-section piston device;

[0013] The slide bar includes a rod and a slide head; the rod and the slide head are fixedly connected to form a T-shaped structure;

[0014] The slide bar is clearance-fitted with the right cavity, and the slide head is clearance-fitted with the right through hole;

[0015] The inner diameter of the right cavity opening is the same as the diameter of the slide bar;

[0016] The right shaft d2 and shaft d4 of the variable cross-section piston device are connected to the left cavity. inner diameter Due to the flattening of the upper and lower surfaces of the d4 shaft, a narrow radial oil outlet is formed in the gap between the left through hole and the two components of the special hydraulic cylinder and the variable cross-section piston device.

[0017] Furthermore: the damping device adopts a flexible mountain-shaped damping device, which includes three sets of equally spaced rectangular spring plates;

[0018] The three sets of equally spaced rectangular spring sheets have the same length and width, and the two outer spring sheets have the same height, which is less than the height of the middle spring sheet.

[0019] In the flexible mountain-shaped damping device, three sets of equally spaced rectangular spring plates are perpendicular to the upper and lower ends of the right through hole.

[0020] The damping device has low bending stiffness and is easy to bend when subjected to axial force from a special hydraulic cylinder, but has high bending stiffness when subjected to force in other directions.

[0021] According to the operating method of the pilot valve stage variable damper described in any one of them: when the slider is embedded between the damping device and the wall of the right through hole, the axial resistance generated is greater than the axial resistance generated when the oil is squeezed out of the narrow radial oil outlet.

[0022] Furthermore, when the slider is not embedded in the damping device, the pilot valve interstage variable damper only provides negligible friction to the outside, therefore this friction cannot cause a relative position change between the variable cross-section piston rod and the special hydraulic cylinder. During this stage, the damping coefficient of the pilot valve interstage variable damper remains zero.

[0023] Furthermore: When the slide bar slides under force to the edge of the right through hole of the special hydraulic cylinder, the slide head is embedded in the flexible mountain-shaped damping device at the left or right end of the right through hole. At this time, the slide head is blocked by the flexible mountain-shaped damping device, causing the slide bar to transmit the force and drive the special hydraulic cylinder to move. This causes the variable cross-section piston rod and the special hydraulic cylinder to change their relative positions, driving the hydraulic oil to flow in or out from the narrow radial oil outlet. As the hydraulic oil flows through the narrow radial oil outlet, the liquid flow area drops sharply, thus generating a throttling effect and providing damping force. During this stage, the damping coefficient of the pilot valve stage variable damper remains at a constant value greater than zero.

[0024] Furthermore: when the damper is applied to a pilot-operated proportional directional valve, it simultaneously connects the pilot stage valve core and the main valve core inside the hydraulic valve;

[0025] When in operation, the pilot valve stage variable damper is aligned with the pilot valve core and the main valve core, transmitting force and motion between the pilot valve core and the main valve core, and providing a variable damping coefficient based on the relative displacement change.

[0026] The present invention provides a pilot valve stage variable damper, the damping of which is achieved by a special hydraulic cylinder. Thus, when the slide rod slides in the hollow cylinder, no resistance is generated. When it moves to the top or bottom of the special hydraulic cylinder, the variable cross section piston rod and the special hydraulic cylinder change relative position to generate a throttling effect to provide resistance. This ensures that the object connected to the damper maintains stability when it moves to the limit position, and does not affect its displacement within a certain range.

[0027] This application relates to a variable damper between pilot valve stages in a pilot-operated proportional directional valve within a hydraulic system. Compared to other dampers, it features variable damping characteristics, a compact structure, the ability to withstand high instantaneous pressure, and smooth movement, ensuring that the valve core can operate smoothly and accurately to the required position.

[0028] This invention utilizes the damping characteristics of a special hydraulic cylinder, which can apply damping at specific positions and ensure the smoothness of the valve core's normal movement. It has a simple structure and is easy to integrate and apply. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the pilot valve stage variable damper;

[0031] Figure 2 This is a schematic diagram of a variable cross-section piston device;

[0032] Figure 3 (a) is a schematic diagram of the flexible mountain-shaped damping device I, and (b) is a schematic diagram of the flexible mountain-shaped damping device II;

[0033] Figure 4 This is a schematic diagram of the operation of the pilot valve stage variable damper;

[0034] Figure 5 This is a diagram showing the damping coefficient-displacement characteristic of the pilot valve stage variable damper.

[0035] Reference numerals: 1. Special type hydraulic cylinder, 2. Variable cross-section piston device, 3. Slide rod, 4. Left through hole, 5. Right through hole, 6. Slide head, 7. Flexible mountain-shaped damping device, 8. Narrow radial oil outlet. Detailed Implementation

[0036] It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0039] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0040] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0041] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways, rotated 90 degrees, or in other orientations, and the spatial relative descriptions used herein will be interpreted accordingly.

[0042] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0043] A pilot valve stage variable damper, comprising

[0044] Special type hydraulic cylinder 1, variable cross-section piston device 2, and slide rod 3;

[0045] The special hydraulic cylinder 1 includes two non-connected cavities, forming a left cavity and a right cavity;

[0046] The left and right cavities contain hydraulic oil; the left and right cavities are concentric with the T-shaped hydraulic cylinder;

[0047] Openings are provided on the left cavity and the right cavity respectively;

[0048] The left and right chambers of the special hydraulic cylinder 1 are respectively provided with rectangular through holes, forming a left through hole 7 and a right through hole 5; wherein, damping devices 6 are provided at both ends of the right through hole 5 near the edge.

[0049] The variable cross-section piston device 2 is a 4-segment shaft, including shaft d1, shaft d2, shaft d3 and shaft d4. The diameters of the 4-segment shaft are d1, d2, d3 and d4 respectively, and the diameter relationship satisfies d4 = d2 > d1 > d3.

[0050] The d1, d2, d3, and d4 axes are fixedly connected in sequence. A schematic diagram of the variable cross-section piston device 2 is shown below. Figure 2 As shown;

[0051] The sum of the lengths of the d1, d2, d3, and d4 axes is greater than the length of the left cavity;

[0052] The slide bar 3 includes a rod and a slide head 4; the rod and slide head 4 are fixedly connected to form a T-shaped structure;

[0053] The slide bar 3 is clearance-fitted with the right cavity, and the slide head 4 is clearance-fitted with the right through hole;

[0054] The right side shafts d2 and d4 of the variable cross-section piston device 2 are fitted with the inner diameter of the left cavity. Since the upper and lower surfaces of shaft d4 are flattened, a narrow radial oil outlet 8 is formed in the gap between the left through hole 7 and the two components of the special hydraulic cylinder 1 and the variable cross-section piston device 2.

[0055] The slide bar has a cylindrical rod portion, and the ratio of the rod portion's length to its diameter is greater than 10.

[0056] The length of the slider 4 is slightly greater than the depth of the right through hole.

[0057] Figure 3 (a) is a schematic diagram of the flexible mountain-shaped damping device I, and (b) is a schematic diagram of the flexible mountain-shaped damping device II;

[0058] The damping device 6 adopts a flexible mountain-shaped damping device, which includes three sets of equally spaced rectangular spring plates.

[0059] The three sets of equally spaced rectangular spring sheets have the same length and width, and the two outer spring sheets have the same height, which is less than the height of the middle spring sheet.

[0060] In the flexible mountain-shaped damping device 6, three sets of equally spaced rectangular spring plates are perpendicular to the upper and lower ends of the right through hole 5.

[0061] The number of spring plates in each group is two;

[0062] The damping device 6 has low bending stiffness and is easy to bend when subjected to axial force from a special hydraulic cylinder, but has high bending stiffness when subjected to force in other directions.

[0063] According to the components in the aforementioned pilot valve interstage variable damper, from left to right, they are: variable cross-section piston rod 2, special-type hydraulic cylinder 1, and slide rod 3. The variable cross-section piston rod 2 engages with the special-type hydraulic cylinder 1 through the left through hole, and the slide rod 3 engages with the special-type hydraulic cylinder 1 through the right through hole. Figure 1 As shown.

[0064] When the slider 4 is embedded between the damping device 6 and the wall of the right through hole, the axial resistance generated is greater than the axial resistance generated when the oil is squeezed out of the narrow radial oil outlet 8.

[0065] The pilot valve interstage variable damper operates as follows: when the slider 4 of the slide rod 3 is engaged with the damping device 6, the pilot valve interstage variable damper only provides negligible frictional force to the outside. Therefore, this frictional force cannot cause a relative position change between the variable cross-section piston rod 2 and the special hydraulic cylinder 1. During this stage, the damping coefficient of the pilot valve interstage variable damper is always zero.

[0066] When the slide rod 3 slides under force to a position near the edge of the right through hole of the special hydraulic cylinder 1, the slide head engages with the flexible mountain-shaped damping device at the left or right end of the right through hole and comes into contact with it. At this time, the slide head 4 is blocked by the flexible mountain-shaped damping device in the right through hole and the left or right end of the right through hole, causing the slide rod 3 to transmit force and drive the special hydraulic cylinder 1 to move. This causes a change in the relative position of the variable cross-section piston rod 2 and the special hydraulic cylinder 1, driving the hydraulic oil to flow in or out of the narrow radial oil outlet 8. Because the liquid flow area of ​​the hydraulic oil drops sharply when it passes through the narrow radial oil outlet 8, a throttling effect is generated, providing damping force. During this stage, the damping coefficient of the variable damper between the pilot valve stages remains a constant value greater than zero. The force analysis diagram between the slide rod and the hydraulic cylinder under external force is shown below. Figure 4 As shown.

[0067] When the damper is applied to a pilot-operated proportional directional valve, it connects both the pilot valve core and the main valve core inside the hydraulic valve.

[0068] When in operation, the pilot valve stage variable damper is aligned with the pilot valve core and the main valve core, transmitting force and motion between the pilot valve core and the main valve core, and providing a variable damping coefficient based on the relative displacement change.

[0069] Within the pilot valve stage, a slide bar is connected to the pilot valve spool, with both objects aligned on the same centerline and in close contact with each other; this connection allows the slide bar to transmit the displacement of the pilot valve spool, and provides resistance to the movement of the pilot valve spool through the system's damping coefficient-displacement characteristics;

[0070] Within the main valve stage, the cross-section piston rod is connected to the main valve core, with the two objects aligned on the same center line and in close contact with each other; this connection causes the piston rod to push the main valve core to move, and provides resistance to the movement of the main valve core through the damping coefficient-displacement characteristics of the system;

[0071] Based on the different resistances generated by the system when the slide rod is located in different positions within the right through hole, a "U"-shaped damping coefficient-displacement characteristic is achieved, such as... Figure 5 As shown.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pilot valve stage variable damper, characterized in that: include Special type hydraulic cylinder (1), variable cross-section piston device (2), and slide rod (3); The special hydraulic cylinder (1) includes two non-connected cavities, forming a left cavity and a right cavity; The cavity contains hydraulic oil; The left and right chambers of the special hydraulic cylinder (1) are respectively provided with rectangular through holes, forming a left through hole (7) and a right through hole (5); wherein, damping devices (6) are provided at both ends of the right through hole (5) near the edge. The variable cross-section piston device (2) is a 4-segment shaft, including shaft d1, shaft d2, shaft d3 and shaft d4. The diameters of the 4-segment shaft are d1, d2, d3 and d4 respectively, and the diameter relationship satisfies d4=d2>d1>d3. The d1, d2, d3, and d4 axes are components of the cross-section piston device; The inner diameter of the left cavity opening is the same as the maximum diameter of the variable cross-section piston device; The slide bar (3) includes a rod and a slide head (4); the rod and the slide head (4) are fixedly connected to form a T-shaped structure; The slide bar (3) is in clearance fit with the right cavity, and the slide head (4) is in clearance fit with the right through hole; The inner diameter of the right cavity opening is the same as the diameter of the slide bar; The right shafts d2 and d4 of the variable cross-section piston device (2) are fitted with the inner diameter of the left cavity. Since the upper and lower surfaces of the d4 shaft are flattened, a narrow radial oil outlet (8) is formed in the gap between the left through hole (7) and the two components of the special hydraulic cylinder (1) and the variable cross-section piston device (2).

2. The pilot valve stage variable damper according to claim 1, characterized in that: The damping device (6) adopts a flexible mountain-shaped damping device, which includes three sets of equally spaced rectangular spring plates; The three sets of equally spaced rectangular spring sheets have the same length and width, and the two outer spring sheets have the same height, which is less than the height of the middle spring sheet. The flexible mountain-shaped damping device (6) has three sets of equally spaced rectangular spring plates perpendicular to the upper and lower ends of the right through hole (5); The damping device (6) has low bending stiffness and is easy to bend when subjected to axial force from the special hydraulic cylinder, but has high bending stiffness when subjected to force in other directions.

3. The pilot valve stage variable damper according to claim 1, characterized in that: When the slider (4) is embedded between the damping device (6) and the wall of the right through hole, the axial resistance generated is greater than the axial resistance generated when the oil is squeezed out of the narrow radial oil outlet (8).

4. The operating method of a pilot valve stage variable damper according to any one of claims 1-3, characterized in that: When the slider (4) is not embedded in the damping device (6), the pilot valve stage variable damper only provides an approximately negligible frictional force to the outside. Therefore, this frictional force cannot drive the variable cross-section piston rod (2) and the special hydraulic cylinder (1) to change their relative positions. The damping coefficient of the pilot valve stage variable damper is always zero.

5. The operating method of a pilot valve stage variable damper according to claim 1, characterized in that: When the slide rod (3) is slid under force to the right through hole of the special hydraulic cylinder (1) near the edge, the slide head is embedded in the flexible mountain-shaped damping device at the left or right end of the right through hole. At this time, the slide head (4) is blocked by the flexible mountain-shaped damping device, causing the slide rod (3) to transmit the force and drive the special hydraulic cylinder (1) to move, causing the variable cross section piston rod and the special hydraulic cylinder (1) to change relative positions, driving the hydraulic oil to flow in or out from the narrow radial oil outlet (8). Since the liquid flow area drops sharply when the hydraulic oil passes through the narrow radial oil outlet (8), a throttling effect is generated to provide damping force. The damping coefficient of the pilot valve stage variable damper is kept at a constant value greater than zero.

6. The operating method of a pilot valve stage variable damper according to claim 1, characterized in that: When the damper is applied to a pilot-operated proportional directional valve, it connects both the pilot valve core and the main valve core inside the hydraulic valve. When in operation, the pilot valve stage variable damper is aligned with the pilot valve core and the main valve core, transmitting force and motion between the pilot valve core and the main valve core, and providing a variable damping coefficient based on the relative displacement change.

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